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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>pencan</b> -  canonical form of matrix pencil</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>[Q,M,i1]=pencan(Fs)  </tt>
      </dd>
      <dd>
        <tt>[Q,M,i1]=pencan(E,A)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>Fs</b>
        </tt>: a regular pencil <tt>
          <b>s*E-A</b>
        </tt>
      </li>
      <li>
        <tt>
          <b>E,A</b>
        </tt>: two real square matrices</li>
      <li>
        <tt>
          <b>Q,M</b>
        </tt>: two non-singular real matrices</li>
      <li>
        <tt>
          <b>i1</b>
        </tt>: integer</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
    Given the regular pencil <tt>
        <b>Fs=s*E-A</b>
      </tt>, <tt>
        <b>pencan</b>
      </tt> returns matrices <tt>
        <b>Q</b>
      </tt> 
    and <tt>
        <b>M</b>
      </tt>
    such than <tt>
        <b>M*(s*E-A)*Q</b>
      </tt> is in "canonical" form.</p>
    <p>
      <tt>
        <b>M*E*Q</b>
      </tt> is a block matrix</p>
    <pre>

[I,0;
 0,N]
   
    </pre>
    <p>
    with <tt>
        <b>N</b>
      </tt> nilpotent and <tt>
        <b>i1</b>
      </tt> = size of the <tt>
        <b>I</b>
      </tt> matrix above.</p>
    <p>
      <tt>
        <b>M*A*Q</b>
      </tt> is a block matrix:</p>
    <pre>

[Ar,0;
 0,I]
   
    </pre>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

F=randpencil([],[1,2],[1,2,3],[]);
F=rand(6,6)*F*rand(6,6);
[Q,M,i1]=pencan(F);
W=clean(M*F*Q)
roots(det(W(1:i1,1:i1)))
det(W($-2:$,$-2:$))
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="glever.htm">
        <tt>
          <b>glever</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="penlaur.htm">
        <tt>
          <b>penlaur</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="rowshuff.htm">
        <tt>
          <b>rowshuff</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
    <h3>
      <font color="blue">Author</font>
    </h3>
    <p>F. D.; ;   </p>
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